Several patents and publications are cited in this description in order to more fully describe the state of the art to which this invention pertains. The entire disclosure of each of these patents and publications is incorporated by reference herein.
Glass laminates are widely used in the automotive and construction industries. A prominent application is in safety glass for automobile windshields. Safety glass is characterized by high impact and penetration resistance and typically consists of a laminate of two glass sheets bonded together with an interlayer of a polymeric film or sheet. One or both of the glass sheets may be replaced with optically clear rigid polymeric sheets, such as sheets of polycarbonate materials. More complex safety glass laminates include constructions that include multiple layers of glass and polymeric sheets that are bonded together with interlayers of polymeric films or sheets.
A safety glass interlayer typically comprises a relatively thick polymer film or sheet that exhibits toughness and bondability and adheres to the glass in the event of a crack or impact. This prevents scatter of glass shards. Generally, the polymeric interlayer is characterized by a high degree of optical clarity and low haze. Resistance to impact, penetration and ultraviolet light is usually excellent. Other properties include long term thermal stability, excellent adhesion to glass and other rigid polymeric sheets, low ultraviolet light transmittance, low moisture absorption, high moisture resistance and excellent long term weatherability. Commonly used interlayer materials include multicomponent compositions based on polyvinyl butyral, polyurethane (PU), polyvinylchloride (PVC), linear low density polyethylenes prepared in the presence of metallocene catalysts, ethylene vinyl acetate (EVA), polymeric fatty acid polyamides, polyester resins, such as polyethylene terephthalate, silicone elastomers, epoxy resins, elastomeric polycarbonates, and the like.
A recent trend has been the use of glass laminated products known as architectural glass in the construction of homes and office structures. Newer products include those specifically designed to resist disasters. Some examples include hurricane resistant glass, theft resistant glazings and blast resistant glass laminated products. Certain of these products have strength sufficient to resist intrusion even if the glass laminate has been broken. Other products meet requirements for incorporation as structural elements within buildings, for example as glass staircases.
It is known to include some form of image or decoration within the laminated glass product. U.S. Pat. Nos. 3,973,058, 4,303,718, and 4,341,683 disclose a process for printing polyvinyl butyral sheet material, used as a component in laminated safety glass, with a solvent-based ink. Disclosures of tint bands are found for example, in U.S. Pat. Nos. 3,008,858; 3,346,526; 3,441,361; and 3,450,552; and in Japanese Patent 2053298.
Disclosures of decorative window films may be found, for example, in U.S. Pat. Nos. 5,049,433, 5,468,532, 5,505,801, and WO 83/03800 which disclose printed window films wherein the film may be affixed to a glass window.
Decorative glass laminates have been produced through the incorporation of decorated films. For example, U.S. Pat. No. 6,824,868, U.S. Patent Application Publication 2003/0203167 and PCT Publication WO 03/092999 disclose an interlayer for laminated glass comprising a polymeric support film with at least one printed color image, a polymeric film bonded to the support film, an adhesive layer bonded to the polymeric support film opposite of the interface between the polymeric support film and the polymeric film and another adhesive layer bonded to the polymeric film opposite of the interface between the polymeric film and the support film. These references teach that laminates of glass and decorated polyvinyl butyral layers would not have the integrity to be used in many applications due to low glass-to-interlayer adhesion. Other references disclosing laminates having printed layers include U.S. Patent Application Publication 2002/0119306, U.S. Patent Application Publication 2003/0091758, and European Patent 0 160 510. European Patent 1 129 844 discloses a composite stratified decorated glass and/or transparent plastic panel characterized in that it comprises first and second glass or transparent plastic panes and a film or sheet made from transparent plastic that bears a decoration. The decorated transparent film or sheet is placed between the two panes and is stably associated with the panes by means of layers of suitable adhesives applied to the panes by calendering or heat lamination. The adhesives include polyurethanes and polyvinyl butyrals. Coating primers, such as silane, polyurethane, epoxy, or acrylic primers may be used on the transparent plastic film. Manufacture of such embedded decorated film laminates is an inefficient method of production.
Decorative glass laminates derived from printed interlayers are known in the art. For example, U.S. Pat. No. 4,968,553, discloses an architectural glass laminate that includes an interlayer of extruded polyurethane, heat-laminated between two sheets of rigid material, wherein a non-solvent based ink containing solid pigments is printed on the polyurethane interlayer prior to lamination. This reference teaches away from the use of polyvinyl butyral as an interlayer material, but decorative polyvinyl butyral sheets produced by transfer processes and used for glass laminates are known. For example, U.S. Pat. Nos. 4,173,672, 4,976,805, 5,364,479, 5,487,939, and 6,235,140 disclose a method for manufacture of decorated colored glass involving transfer of a color impression onto an adhesive polyvinyl butyral layer. Ink jet printing a temporary substrate and transfer printing the image onto a second substrate is disclosed in WO 95/06564 and WO 2004/039607.
Decorative printed polyvinyl butyral sheets for glass laminates are also known in the art. U.S. Pat. No. 5,914,178 discloses a laminated pane which comprises at least one visible motif, the pane comprising at least one rigid sheet of a glass material or a plastics material and at least one sheet of flexible plastics material. The motif is at least partly formed of at least one coating of organic ink epoxy layer. The reference discloses that polyvinyl butyral and polyurethane plastics materials may be utilized.
U.S. Patent Application Publication 2004/0187732 discloses an ink jet ink set comprising non-aqueous, colored, pigmented inks, at least one of which is a yellow ink comprising PY120 dispersed in a non-aqueous vehicle. The use of this ink set in ink jet printing of, for example, polyvinyl butyral substrates is disclosed, as is the use of the printed substrate in preparation of laminated glass articles. U.S. Patent Application Publication 2004/0234735 and WO 02/18154 disclose a method of producing image carrying laminated material including the steps of forming an image on a first surface of a sheet of interlayer using solvent based ink, paint or dye systems, interposing the interlayer sheet between two sheets of material and joining the two sheets of material to form the laminate by activating the interlayer. WO 2004/011271 discloses a process for ink-jet printing an image onto a rigid thermoplastic interlayer, wherein the interlayer has a Storage Young's Modulus of 50-1,000 MPa. WO 2004/018197 discloses a process for obtaining an image-bearing laminate having a laminate adhesive strength of at least 1000 psi, which includes ink jet printing a digital image onto a thermoplastic interlayer selected from polyvinyl butyrals, polyurethanes, polyethylenes, polypropylenes, polyesters, and EVA using a pigmented ink which comprises at least one pigment selected from the group consisting of PY120, PY155, PY128, PY180, PY95, PY93, PV19/PR202, PR122, PR15:4, PB15:3, and PBI7.
Reduction of energy consumption within structures in which glass is applied is very desirable and has led to development of solar control glass structures. Typical solar control glass is designed to eliminate or reduce energy from the near infrared region of the electromagnetic spectrum. For example, the air conditioning load may be reduced in buildings equipped with solar control windows which block out a portion of the near infrared region of the solar spectral range. Solar control glass laminates may be obtained by modification of the glass itself, by modification of polymeric interlayers used in laminated glass, and by the addition of further solar control layers, such as in window films. Metal oxide nanoparticles are often used in solar control layers to absorb infrared light and convert energy to heat. Materials having nominal particle sizes below about 50 nanometers are used to preserve the clarity and transparency of the substrate. Infrared-absorbing nanoparticles of commercial significance are antimony tin oxide and indium tin oxide. Processes to produce antimony tin oxide particles and indium tin oxide particles are disclosed in U.S. Pat. Nos. 4,478,812; 4,937,148; 5,075,090; 5,376,308; 5,772,924; 5,807,511; 5,518,810; 5,622,750; 5,958,631; 6,051,166 and 6,533,966.
Antimony tin oxide nanoparticles and indium tin oxide nanoparticles have been incorporated into polymeric interlayers of glass laminates. Laminated glass which incorporates homogeneously dispersed, functional, ultra-fine particles is disclosed in U.S. Pat. Nos. 5,830,568; 6,315,848; 6,329,061; and 6,579,608. Laminated glass that includes indium tin oxide particles dispersed within plasticized polyvinyl butyral interlayers and certain types of glass is disclosed in U.S. Pat. Nos. 6,506,487 and 6,686,032. U.S. Pat. No. 6,632,274 discloses ultrafine particle dispersions in a plasticizer and their use in polyvinyl butyral interlayers for glass laminates. U.S. Pat. Nos. 6,620,477, 6,632,274 and 6,673,456 disclose laminated glass that contains indium tin oxide particles dispersed within certain plasticized polyvinyl butyral interlayers. U.S. Pat. No. 6,733,872 discloses sound proofed glass laminates which include indium tin oxide particles dispersed within plasticized polyvinyl butyral interlayers. European Patent Application 1 227 070 A1 discloses an interlayer for laminated glass comprising an adhesive resin.
Antimony tin oxide and indium tin oxide nanoparticles have also been incorporated into coatings. Particle dispersions, coating solutions, and coated substrates of these substances are disclosed in U.S. Pat. Nos. 5,376,308; 5,504,133; 5,518,810; 5,654,090; 5,662,962; 5,742,118; 5,763,091; 5,772,924; 5,807,511; 5,830,568; 6,084,007; 6,191,884; 6,221,945; 6,261,684; 6,277,187; 6,315,848; 6,319,613; 6,329,061; 6,404,543; 6,416,818; 6,506,487; 6,528,156; 6,579,608; 6,620,477; 6,632,274; 6,663,950; 6,673,456; 6,686,032; 6,733,872; European Patent 947 566; and European Patent Application 1 154 000 A1. For example, U.S. Pat. No. 5,807,511 discloses a near infrared screening filter composition which includes a metal oxide or inorganic oxide powder and a dye. Japanese Patent Publication 2004124033 discloses a coating material which includes electrically conductive transparent ultrafine particles and a polyester substrate coated with the material that produces an infrared-shielding film.
Film substrates coated with antimony tin oxide and indium tin oxide materials have been disclosed as solar control window coverings. U.S. Pat. No. 5,518,810, discloses the use of indium tin oxide and antimony tin oxide particles in infrared ray cutoff coatings. U.S. Pat. Nos. 6,191,884, 6,261,684 and 6,528,156 disclose coatings that contain indium tin oxide particles useful as solar control window films. The films may be attached to windows with a thin layer of contact adhesive.
Metal boride nanoparticles have also been utilized to absorb infrared light and convert energy to heat. To preserve the clarity and transparency of the substrate these materials have nominal particle sizes below about 200 nanometers (nm). Metal boride nanoparticles are reported to be more efficient than metal oxide nanoparticles, resulting in the use of significantly reduced levels of the former to attain equivalent performance. Infrared-absorbing metal boride nanoparticles include lanthanum hexaboride. These materials may be produced as disclosed in Japanese Patent Publications 2004277274; 2004237250; 2003321218; 2003277045; and 2003261323. U.S. Pat. No. 6,060,154 discloses a coating solution that contains lanthanum hexaboride nanoparticles and solar control films produced therefrom. U.S. Pat. Nos. 6,221,945 and 6,277,187 disclose a coating solution containing lanthanum hexaboride nanoparticles and solar control films produced by coating the nanoparticles onto a substrate. U.S. Pat. No. 6,319,613 and European Patent 1 008 564 disclose coating solutions containing a combination of lanthanum hexaboride and antimony tin oxide or indium tin oxide nanoparticles for use in solar control window covering films. U.S. Pat. No. 6,663,950 discloses solar control window films comprising a transparent polymeric film substrate having a UV-absorbing material coated with a hardcoat layer. Polymeric dispersions of lanthanum hexaboride nanoparticles are disclosed in U.S. Pat. No. 6,673,456. WO 02/060988 discloses glass laminates prepared from polyvinyl butyral resin containing lanthanum hexaboride or a mixture of lanthanum hexaboride and indium tin oxide or antimony tin oxide. Master batch compositions containing lanthanum hexaboride nanoparticles in a thermoplastic resin are disclosed in U.S. Published Patent Application 2004/0028920.
A shortcoming of solar control laminates which incorporate infrared absorptive materials is that a significant proportion of the light absorbed serves to generate heat. This is especially true when the laminates are used in structures such as parking garages. In such situations, reflective solar control laminates are desirable because they do not increase in temperature by absorbing solar energy.
Metallized substrate films have been used in solar control laminates. These include polyester films which have electrically conductive metal layers, such as aluminum or silver metal, typically applied through a vacuum deposition or a sputtering process. These structures and their use in glass laminates is disclosed in U.S. Pat. Nos. 3,718,535; 3,816,201; 3,962,488; 4,017,661; 4,166,876; 4,226,910; 4,234,654; 4,368,945; 4,386,130; 4,450,201; 4,465,736; 4,782,216; 4,786,783; 4,799,745; 4,973,511; 4,976,503; 5,024,895; 5,069,734; 5,071,206; 5,073,450; 5,091,258; 5,189,551; 5,264,286; 5,306,547; 5,932,329; 6,391,400 and 6,455,141. U.S. Pat. Nos. 4,782,216 and 4,786,783 disclose a transparent, laminated window with near IR rejection that includes two transparent conductive metal layers. U.S. Pat. No. 4,973,511 discloses a laminated solar window construction which includes a PET sheet with a multilayer solar coating. U.S. Pat. No. 4,976,503 discloses an optical element that includes light-reflecting metal layers. Reflecting interference films are disclosed in U.S. Pat. No. 5,071,206. U.S. Pat. No. 5,091,258 discloses a laminate that incorporates an infra-red radiation reflecting interlayer. A laminated glass pane having a transparent support film of tear-resistant polymer provided with an IR-reflecting coating and two adhesive layers is disclosed in U.S. Pat. No. 5,932,329. U.S. Pat. No. 6,204,480 discloses thin film conductive sheets for windows while U.S. Pat. No. 6,391,400 discloses dielectric layer interference effect thermal control glazings for windows. U.S. Pat. No. 6,455,141 discloses laminated glass that incorporates an interlayer having an energy-reflective coating. European Patent 0 418 123 discloses laminated glass with an interlayer comprising a copolymer of vinyl chloride and glycidyl methacrylate.
Heretofore it has not been known to combine the benefits of decorative glass laminates with the benefits of solar control glass laminates.